Sen. Richard Shelby (R-AL), chairman of the subcommitteeSenate Appropriations Committee panel that oversees the Department of Justice said, "The department is on notice. This subcommittee will have no part in undermining the Constitution and the rights that it protects."

Other GOP senators on the panel, though disliking Obama's actions, seemed open to some aspects of expanding background checks for guns.

"As the list of tragedies involving firearms has grown, so has the American people's belief that we must do more to stem the tide of gun violence, and this administration is committed to doing our part," she said.